Medicine and Health Sciences Commons^™

Rapid Recovery Of Cerebral Blood Content And Oxygenation In Adults From Time-Resolved Near-Infrared Spectroscopy, David J. F. Cohen

Electronic Thesis and Dissertation Repository

Patient neurological outcomes following cardiac surgery are improved when near-infrared spectroscopy (NIRS) is used to optimize intraoperative cerebral oxygen delivery. However, current NIRS analysis methods have difficulties monitoring adult brains due to contamination from the extracerebral layer (ECL).

The objective of this thesis is to develop a time-resolved (TR) NIRS data analysis method for monitoring adult cerebral oxygen saturation (ScO2) and total hemoglobin (HbT) by assuming the head is composed of two layers – the ECL and the brain. We tested the validity of this assumption using in silico data from an adult human head using two approaches; a few-wavelength, …

The Effects Of Exercise On Cognition, Mobility, And Neuroimaging Outcomes In Older Adults Without Dementia, Narlon Cassio Boa Sorte Silva

Electronic Thesis and Dissertation Repository

Cognitive decline is increasing with the aging population and, at present, there is no effective pharmacologic treatment available. Exercise interventions may impart protection against cognitive decline. A novel exercise approach is multiple-modality exercise (MME; aerobic, resistance, and balance exercise) with mind-motor training. Mind-motor training is a promising intervention in the study of cognitive function. Combining MME with mind-motor training may improve or maintain cognition and provide prevention of dementia early in the course of cognitive decline. Individuals with subjective cognitive complaints (SCC) comprise an at-risk group early in the spectrum of cognitive decline that could be targeted for prevention. The …

Is Allocation Of Attention Impaired In Fallers Compared To Non-Fallers? An Event-Related Potential Study, Phil Parrot-Migas

Electronic Thesis and Dissertation Repository

Approximately 30% of older adults experience one or more falls annually. The ability to properly allocate attention may be a risk factor falls. Our study examined whether older adults (aged 58-79) with a history of falls, allocated attention differently to auditory distractor stimuli compared to those without a history of falls, and whether such differences subsequently altered cognitive processing of visual target stimuli. We examined allocation of attention using event-related potentials (ERPs) as participants responded to visual targets while ignoring task-irrelevant auditory distractors. A posterior to anterior shift in electrical brain activity was exaggerated in the faller group compared to …

Measuring Brain Serine With Proton Magnetic Resonance Spectroscopy At 3.0 Tesla, Homa Javadzadeh

Electronic Thesis and Dissertation Repository

Proton magnetic resonance spectroscopy (MRS) non-invasively measures regional human brain chemistry in vivo, providing concentration estimates for several metabolites in a pre-selected region of interest. MRS has been applied to investigations of disease-related metabolic and neurochemical alterations in schizophrenia since the early 90’s.

The objective of this research is to implement a metabolite-selective MRS method to quantify endogenous concentrations of human brain serine. Serine is a naturally-occurring amino acid and an important co-modulator of the N-Methyl D-aspartic Acid (NMDA) glutamate receptor. Glutamate abnormalities have been implicated in the pathophysiology of schizophrenia, especially its so-called negative and cognitive symptoms, which can …